Tracking Junk
Thursday, September 4th, 2014September 4, 2014
American aerospace firm Lockheed Martin and a telescope company based in Canberra, Australia—Electro Optic Systems (ELO)—have partnered to track junk. Space junk.
Space seems like a silent, empty place in movies. While it may be silent, it is certainly not empty. It is filled with junk—human-made, nonworking objects that orbit Earth. The National Aeronautics and Space Administration (NASA) estimates there are more than 20,000 pieces of such debris of a size larger than a softball (12 inches [30 centimeters] in circumference) orbiting our planet.
The junk circling Earth is composed of many things. When astronauts threw out a bag of garbage from the International Space Station or Mir, that bag became space junk. When an astronaut working outside a spacecraft dropped and lost a tool, that floating tool became more space junk. Even tiny items, such as specks of paint and drops of frozen liquid, become part of the debris circling in space.
All of this debris matters because it can be dangerous. Space junk travels at speeds up to 17,500 miles (27,000 kilometers) per hour—the speed required for objects to stay in an orbit around Earth. At such speeds, even tiny objects can damage or destroy a satellite or spacecraft. For example, in 2009, a nonfunctioning Russian satellite collided with and destroyed a functioning U.S. commercial satellite. Satellites are expensive, so the loss of the commercial satellite was bad enough. But, when such events happen, they also add to the problem. The collision between the Russian and American satellites created thousands of pieces of new space junk. According to experts, one satellite a year is lost on average, owing to a collision with debris.
Space junk is currently tracked using several radar systems, including the U.S. Air Force Space Fence system. The new system to be built by EOS will use advanced optical and laser technology to track pieces as small as a golf ball (1.68 inches [4.27 centimeters] in diameter)—a much smaller size than current technology permits. The site to track space junk will be housed in western Australia and it is estimated that it will cost $75 million to build. The hope is that this new system will save satellites worth millions of dollars and will increase safety for humans traveling through the region where much of the debris exists.
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